Molybdenum alloys



Patented Jan. 30, 1940 UNITED STATES MOLYBDENUM ALLOYS Franz R. Henseland Kenneth L. Emmert, Indianapolis, Ind., assignors to P. R. Mallory &00., Inc., Indianapolis, Ind.,a corporation of Delaware No Drawing.Application February 11, 1939, Serial No. 255,871

2 Claims.

This invention relates to improvements in molybdenum base alloys.

It is the object of the invention to provide a material which possessessuperior physical properties such as high specific gravity andsatisfactory strength. Such a material is suitable for X-ray targets.

It is also an object of the present invention to provide a contactmaterial of superior properties.

It is a further object of the invention to provide a material of highmelting point and high recrystallization temperature.

Other objects of the invention will be apparent from the followingdescription taken in connection with the appended claims.

The present invention comprises a combination of elements, methods ofmanufacture and the product thereof brought out and exemplified in thedisclosure hereinafter set forth, the scope of the invention beingindicated in the appended claims.

While a preferred embodiment of the invention is described herein, it iscontemplated that considerable variation may be made in the meth od ofprocedure and the combination of elements without departing from thespirit of the invention.

According to the present invention an improved alloy is contemplated,having the following ingredients present in substantially theranges ofproportion given below:

Per cent Molybdenum 60 to 99.75 Osmium .01 to 1 denum in solid solutionand part of which exists as a free constituent, the bonded alloysshowing increased hardness and considerable resistance to abrasion.Osmium is suitable as an alloy element for molybdenum because it has amelting point similarly high, the actual melting temperature being about2700 centigrade while the boiling point is in the neighborhood of 5000centigrade. Osmium in molybdenum can be sintered by heating to atemperature of about 2000 centigrade. Since the oxide of osmium can bereadily reduced by hydrogen, the sintering can be carried out in ahydrogen atmosphere. It is also possible to produce molybdenum 01' highdensity by sintering only if small additions of osmium are being made.In our experiments we have found that alloys up to approximately to l%of osmium in molybdenum can be manufactured by mixing thepowders,,subjecting same to a high pressure to form an ingot. The ingotor special shapes then may be sintered and forged .or swaged, rolled ordrawn to a convenient shape from which the various parts can bemanufactured, forwlrrlch this alloy is particularly suitable. It isunderstood that one or more ofthe ingredients can be present originallyin the form of chemical compounds and can be reduced a. gether to themetallic state.- Binary alloys containing more than 1% of osmium arediflicult to swage and must be manufactured by sintered process only.This swaging difliculty, however, can be overcome if other elements ofthe tungsten group are added. The desirable characteristics describedabove will not be disturbed if small proportions of other ingredientsare present from the iron group materials such as iron-cobalt and nickelor small percentages of tantalum, columbium, chromium and manganese.

We can use our new alloying composition as a refractory base for amaterial composition consisting of molybdenum containing substantialquantities of osmium impregnated with low. melting point materials takenfrom the group copper, silver, gold, platinum and palladium and theiralloys.

' Since certain changes in producing the above alloy and certainmodifications in the composition which embody the invention may be made,without departing from its scope, it is intended that all mattercontained in the above description shall be interpreted as illustrativeand not in a limited sense.

It is also to be understood that the following claims are intended tocover all of the generic 40 and specific features of the inventionherein described and all statements of the scope of the invention, whichas a matter of language might be said to fall therebetween.

What is claimed is:

1. An alloy formed of .01 to 1% osmium and the balance substantially allmolybdenum.

2. An electric contact formed of an alloy of .01 to 1% osmium and thebalance substantially all molybdenum. A

FRANZ R. HENSEL. 1

ENNETH L. EMMERT.

